Preparing a Wet Mount
•
•
•

Using a pipet or dropper, add a drop of water or
another solvent to a clean microscope slide....
•
•
•

increases visibility of specimen
accentuates specific morphological features
preserves specimens


Process by which internal and external
structures are preserved and fixed in
position. Organisms are also killed and
fi...


Dyes
 make internal and external structures of cell
more visible by increasing contrast with
background
 have two com...


simple staining
 a single staining agent is used
 basic dyes are frequently used
▪ dyes with positive charges
▪ e.g.,...


divides microorganisms into groups based on
their staining properties
 e.g., Gram stain
 e.g., acid-fast stain



most widely used differential staining
procedure
divides Bacteria into two groups based on
differences in cell wall s...
primary
stain

Gram Stain
Procedure

mordant

decolorization
counterstain
positive
negative
Gram stain of Escherichia coli


Negative staining
 often used to visualize capsules surrounding

bacteria
 capsules are colorless against a stained
b...
Specimen prep
Specimen prep
Upcoming SlideShare
Loading in …5
×

Specimen prep

238 views

Published on

Intro to the Lab Specimen Prep PP

Published in: Technology, Business
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
238
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
9
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Specimen prep

  1. 1. Preparing a Wet Mount • • • Using a pipet or dropper, add a drop of water or another solvent to a clean microscope slide. Then, place the specimen in the water. Place the edge of a coverslip on the slide so that it touches the edge of the water. Slowly lower the coverslip to prevent the formation of air bubbles.
  2. 2. • • • increases visibility of specimen accentuates specific morphological features preserves specimens
  3. 3.  Process by which internal and external structures are preserved and fixed in position. Organisms are also killed and firmly attached to microscope slide.  heat fixing ▪ preserves overall morphology but not internal structures  chemical fixing ▪ protects fine cellular substructure and morphology of larger, more delicate organisms
  4. 4.  Dyes  make internal and external structures of cell more visible by increasing contrast with background  have two common features ▪ chromophore groups ▪ chemical groups with conjugated double bonds ▪ give dye its color ▪ ability to bind cells
  5. 5.  simple staining  a single staining agent is used  basic dyes are frequently used ▪ dyes with positive charges ▪ e.g., crystal violet
  6. 6.  divides microorganisms into groups based on their staining properties  e.g., Gram stain  e.g., acid-fast stain
  7. 7.   most widely used differential staining procedure divides Bacteria into two groups based on differences in cell wall structure
  8. 8. primary stain Gram Stain Procedure mordant decolorization counterstain positive negative
  9. 9. Gram stain of Escherichia coli
  10. 10.  Negative staining  often used to visualize capsules surrounding bacteria  capsules are colorless against a stained background

×